Filter cavities of the type described for instance in my prior U.S. Pat. No. 4,249,147 and intended to be used in forming a multicoupler system have heretofore been mounted on commercially available steel relay racks comprising a pair of side panels arranged to upstand in a parallel relationship from a common base and a top panel for connecting the upper ends of the side panels, whereby to define a rigid open ended structure. Typically, in racks of this type, the side panels are fitted with flanges having apertures intended to receive threaded fasteners or bolts for use in mounting a plurality of shelves to extend horizontally between the side panels and in a vertically spaced relationship. To adapt these racks for use in supporting cylindrically shaped filter cavities, it was necessary to replace the shelves with pairs of aluminum cross bars, which had their opposite ends fixed to the side panel flanges and were in turn fitted with aligned pairs of upstanding mounting flanges spaced lengthwise of their associated cross bars to engage with circumferentially spaced portions of the cylindrical side surface of each filter cavity adjacent its opposite ends. The ends of the filter cavities were then clamped to each associated pair of mounting flanges by a pair of conventionally metal binder straps arranged to encircle such ends and pass through holes punched in the mounting flanges.
This prior arrangement suffered from the drawback that commercially available steel racks are expensive, quite heavy and require large fixed size installation spaces, which may result in substantial waste in such space when a particular installation does not require a sufficient number of cavity filters to fill a given conventionally sized rack to capacity.